FIG. 1 is an illustration of a conventional seal ring 100 for a semiconductor die 110, shown in both a top-down view and cross sectional view. The seal ring 100 circumscribes the periphery of the semiconductor die 110 and helps to isolate the semiconductor die 110 from moisture and contamination and stops cracks caused during dicing. The seal ring 100 is built on a silicon substrate 101 and includes contact 102, vias 104 and 106, and metal segments 103, 105, and 107.
The semiconductor die 110 includes a variety of components, such as a digital logic circuit 111, an analog block 112, and Radio Frequency (RF) blocks 113, 114. Some conventional digital logic circuits, such as the circuit 111 are subject to sudden spikes in current that cause noise, whereas some conventional analog blocks and RF blocks (e.g., blocks 112-114) can be sensitive to noise.
Some conventional seal rings (not shown) are electrically continuous around the periphery of a die, and the direct electrical path around the periphery of the die can transfer five to ten decibels of noise to sensitive analog and RF blocks, which is undesirable. One conventional solution to prevent noise transfer is shown in the top-down view of FIG. 1. Specifically, the seal ring 110 is electrically discontinuous, thereby inhibiting a significant portion of the noise transfer. The solution shown in the top-down view of FIG. 1 can be effective to eliminate some of the noise, but the discontinuities of the seal ring 100 allow for penetration of the semiconductor die 110 by harmful moisture and other contaminants. Currently, there is no available solution that reduces the noise phenomenon described above while also preventing penetration of the semiconductor die 110 by moisture and contaminants.